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Version 150 (modified by viboes, 11 years ago) ( diff )
Added Generic & TypeErasure

Libraries Under Construction
Other Open Source libraries
1. ASL
2. async
3. coco
4. Poet
5. TBB
6. tscb
Libraries Wish list
1. Accumulators.Ext
2. Association
3. Cloner
4. CallStack
5. ConstraintsProgramming
6. Databases
7. Enums
8. EnumSet
9. EnumArray
10. Frames
11. ObjectRole
12. Quartets
13. SpreadSheet
Abandoned
1. Boost.ConceptTraits
Libraries Listed by Category

WARNING: The contents of this page could be incomplete and outdated. Please help us to improve this page by modifying it directly or posting on the Boost mailing lists boost-AT-lists.boost.org or boost-users-AT-lists.boost.org with the prefix `[LibrariesUnderConstruction].

See Boost Releases documentation for the list of libraries Boost by release. See Boost Review Schedule for Boost ongoing details.

Most of the ongoing libraries are stored on the SVN Sandbox, the Boost Vault or on specific sites.

Libraries Under Construction

This page is an index page for libraries under construction.

Boost.AllocPlus

Author(s): Ion Gaztañaga igaztanaga-AT-gmail.com
Version:
State:
Last upload:
Links: Documentation Download
Categories: Memory
Description:Allocators optimizations

Boost.Asio.eos_portable_archive

Author(s): Ion Gaztañaga igaztanaga-AT-gmail.com
Version:
State:
Last upload:
Links: Documentation Download
Categories: Concurrent Programming
Description:portable archive

Boost.Async

Author(s): Vicente J. Botet Escribá
Version: 0.2
State: Quite Stable
Last upload: 2009 May 24
Links: Boost Vault Boost Sandbox Documentation
Categories: Concurrent Programming Containers
Description: Asynchronous Executors (AE) and Asynchronous Completion Tokens (ACT) in a generic way (or at least this was my intention). The library can be considered as a front-end for several Asynchronous Execution models making it possible to share common algorithms and making easier to switch from an Asynchronous Executors to another.

Next follows the motivation for the library and how the library can manage with this concepts.

In N1833 - Preliminary Threading Library Proposal for TR2 Kevlin Henney introduce the concept of threader and a function thread that evaluate a function asynchronously and returns a joiner handle. In N2185 - Proposed Text for Parallel Task Execution Peter Dimov introduce a fork function able to evaluate a function asynchronously and returns a future handle. In N2276 - Thread Pools and Futures Anthony William introduce launch_in_thread and launch_in_pool function templates which evaluate a function asynchronously either in a specific thread or a thread pool and returns a unique_future handle. In Boost.ThreadPool Oliver Kowalke propose a complete implementation of a thread pool with a submit function which evaluate a function asynchronously and returns a task handle.

Behind all these proposal there is a concept of asynchronous executor, fork-launch-like function and the asynchronous completion token handle.

Name	executor	fork-like	ACT
Boost.Thread	??	thread constructor	thread
Boost.ThreadPool	tp::pool	submit	tp::task
N2276	thread	launch_in_thread	unique_future<T>
N2276	thread_pool	launch_in_pool	unique_future<T>
N2185	??	fork	future<T>
N1833	threader	thread	joiner<T>

The asynchronous completion token models can follows two interfaces, the thread interface and the unique_future interface. Some asynchronous completion token handles allows to recover the result of the evaluation of the function (futures), other allows to manage the underlying thread of execution (thread) and some both (joiner and tp::task).

It seems natural to make a generic fork function that will evaluate a function asynchronously with respect to the calling thread and returns an ACT handle. The following meta-function associated an ACT handle to a asynchronous executor.

template <typename AE, typename T>
struct asynchronous_completion_token {
    typedef typename AE::template handle<T>::type type;
};

The result of forking a nullary function by an asynchronous executor is given by the following meta-function:

namespace result_of { 
    template <typename AE,typename F>
    struct fork {
        typedef typename asynchronous_completion_token<AE, typename result_of<F()>::type>::type type;
    };   
}

The default implementation of fork delegates on fork asynchronous executor function.

template< typename AE, typename F > 
result_of::fork<AE, F>::type fork( AE& ae, F fn ) {
    return ae.fork(fn);
}

Forking n-ary functions relies on the nullary version and bind.

template< typename AE, typename F, typename A1, ..., typename An > 
asynchronous_completion_token<AE, typename result_of<F(A1,..., An)>::type >::type 
fork( AE& ae, F fn, A1 a1, ..., An an ) {
    return ae.fork( bind( fn, a1, ..., an ) );
}

Boost.Async is a C++ library to allow the calling of functions and functors in an asynchronous manner, thereby making it easier to improve the level of concurrency and parallelism in your applications. It provides:

An asynchronous execution framework working with AsynchronousExecutor and AsynchronousCompletionToken. It includes some generic functions and several AsynchronousExecutor and AsynchronousCompletionToken:
- fork and fork_all to execute asynchronously functions
- fork_after: request an AsynchronousExecutor to execute a function asynchronously once each one of AsynchronousCompletionToken in the dependency tuple parameter are ready. It is similar to the async_with_dependencies proposed Peter Dimov.
- generic get, join, ... free functions to synchroyze on an AsynchronousCompletionToken
- generic get_all, join_all, ... free functions to synchroyze on multiple AsynchronousCompletionToken
- generic wait_for_all, wait_for_any to execute asynchronously functions and wait for the completion of all or any of them.
Some AsynchronousExecutor and AsynchronousCompletionToken models
- inmediate executors: executes synchronously a function on the current thread. Often used for test purposes
- basic_threader: can be seen as a thread factory executing asynchronously a function on the returned thread.
- launchers: Lanchers can be seen as a future factory executing asynchronously a function on a hidden thread.
- threader/joiner: A Threader runs a unary function in its own thread. A Threader can be seen as a Joiner factory executing asynchronously a function on a thread encapsulated on the returned Joiner. The joiner is used to synchronize with and pick up the result from a function or to manage the encapsulated thread.
- tp::pool and tp::task customization as an AsynchronousExecutor and an AsynchronousCompletionToken respectively. tp::pool can be seen as a tp::task factory executing asynchronously a function on a pool of threads.
- a generic asynchronous_executor_decorator which allows to decorate the function to be evaluated asynchronously.

Boost.Atomic

Author(s): Helge Bahmann
Version:
State: On going
Last upload: 2009 November 29
Links: Web page
Categories: Concurrent Programming
Description: Implementing C++0x atomics for boost

The purpose of this library is to provide an implementation of atomic operations for boost, based on the interface specified by the C++0x draft standard. It aims to make transitioning to std::atomic easy, as well as providing a means to make code using this C++0x feature compilable on older systems.

Boost.AutoFunction

Author(s): Matt Calabrese
Version: 0.0.0
State: On going
Last upload: 2010 October 10
Links: Boost Sandbox Documentation
Categories: Utilities Generic Programming
Description: Boost.Auto_Function is a library focused on making it simple for programmers to express functions and function declarations that have an automatically deduced return type and to provide a way to place arbitrary compile-time requirements on a function's signature.

Boost.Bitfield

Author(s): Emile Cormier, Vicente J. Botet Escribá
Version: 0.2
State: Ready
Inclusion date: 2009 May 4
Last upload: 2009 October 15
Depends on: Endian
Links: Boost Vault Boost Sandbox Documentation
Categories: Endian Portability, Integers
Description:Portable bitfields traits
- a generic bitfield traits class providing generic getter and setter methods.
- a BOOST_BITFIELD_DCL macro making easier the definition of the bitfield traits and the bitfield getter and setter functions.

    struct X {
        typedef boost::ubig_32 storage_type;
        storage_type d0;
        typedef unsigned int value_type;
        BOOST_BITFIELD_DCL(storage_type, d0, unsigned int, d00, 0, 10);
        BOOST_BITFIELD_DCL(storage_type, d0, unsigned int, d01, 11, 31);
    };

Boost.BloomFilters

Author(s): Dean Michael Berris
Version: 0.1
State: On going
Last upload: 2009 June 08
Links: Boost Sandbox
Categories: Containers
Description:Bloo Filters

A Bloom Filter is a space efficient data-structure that allows you to represent set membership that allows for false positives (elements may have been marked as included in a set when they really aren't part of the set) but not false negatives (when an element has not been included/added in the set, the bloom filter wouldn't show that they are part of the set). These have been used in proxy caches to signify whether they already have a cached copy of a URI. File systems also use these to see whether a part of a file (or a page) has already been accessed before (to limit the frequency of fetching pages that have been fetched before on a DFS for instance).

A more in-depth explanation of bloom filters can be found here: http://en.wikipedia.org/wiki/Bloom_filter

Boost.Channel

Author(s): Yigong Liu
Version: 0.4
State: Stable
Last upload:Jul 15, 2008
Links: Web Site Boost Vault
Categories: Distribution
Description: Channel is a C++ framework for distributed message passing and event dispatching, configurable with its components (msg ids,routing algorithms...) as template parameters. As a namespace shared by peer threads, channel supports scope control and filtering.

Boost.CLI

Author(s): Jean-Daniel Michaud
Version:
State:
Last upload: 2007
Links: Boost Vault
Categories: Input/Output
Description: .

Boost.Cloneable

Author(s): Christian Schladetsch
Version: 0.1
State:
Last upload: 2009 July 08
Links: Boost Sandbox
Categories: Containers Data Structures Utilities
Description: The Boost.Cloneable library provides a means for creating, duplicating, and querying instances of object types that are specified in class hierarchies, and a set of containers for those objects.

Cloneable objects can create clones of derived types from base types, can do so given any STL-compliant allocator, and supports multiple clone type targets.

The user of the library is able to override the default cloning process, and may supply custom allocators. Cloneable types can derive from other cloneable types, in which case the user can specify which subobject type to duplicate or create when making a new clone or new object from an existing instance.

You can use Boost.Cloneable with existing, external types without modification to those types by using the supplied adaptor mechanism. Boost.Cloneable also supports types that are not default-constructable.

There is a fundamental requirement that a common base class type is shared for each type in a given class hierarchy. The user can supply their own base classes, or sensible defaults are generated.

Key features of the library:

Can make any class-type Cloneable with or without modification to its definition
Optional user-supplied base classes
Base types can be queried for the interfaces they support
Clones can be created from base types
Supports multiple inheritance, cloning of sub-objects
Supports types with no default constructors
Customisation of the cloning process
Support for custom allocators
A set of heterogenous containers with emplace semantics for object insertion

Boost.ClonePtr

Author(s): Rafal Moniuszko
Version:
State:
Last upload: 2010 May 25
Links: Download
Categories: Data Structures Utilities
Description: We can think about clone_ptr in two different ways:
- as auto_ptr with different copy semantics (this is exactly what clone_ptr is)
- as one-element ptr_container

clone_ptr frees programmer from managing pointer the same way ptr_container for container of pointers does.

Boost.Contract

Author(s): Lorenzo Caminiti
Version: 0.0.1
State: Prototype
Last upload:
Links: Download Documentation
Categories: Correctness And Testing
Description: Implement Contract Programming for C++.

Contract Programming is also known as Design by Contract(TM) and it was first introduced by the Eiffel programming language. All Contract Programming features of the Eiffel programming language are supported by this library, among others:

Optional compilation and checking of invariants, preconditions, and postconditions.
Customizable actions on contract failure (terminate by default but it can throw, exit, etc).
Subcontracting for derived classes (with support for pure virtual functions and multiple inheritance).
Access to "old" variable values (before body execution) and return value "result" in postconditions.
Support block invariants and loop variants.

In brief, Contract Programming allows to specify invariants, preconditions, and postconditions that are automatically checked when functions are called at run-time. These conditions are used to assert the function specifications within the source code itself allowing to find bugs more quickly during testing and improving software quality.

Boost.Construe

Author(s): Jeroen Habraken
Version: 0.2
State: On going
Last upload: 2010 October 07
Links: Repository
Categories: Utilities
Description: Builds upon boost.spirit to create a cast-like operator aiming to

provide an alternative to lexical_cast providing greater speed and flexibility.

Boost.ConstantTimeSize

Author(s): Vicente J. Botet Escribá
Version: 0.1
State: Stable
Last upload:2008 Oct 14
Links: Boost Vault Boost Sandbox
Categories: Containers
Description: Boost.ConstantTimeSize defines a wrapper to the STL container list giving the user the choice for the complexity of the size function: linear time, constant time or quasi-constant.

In future versions the library could include a similar wrapper to slist.

Boost.Convert

Author(s): Vladimir Batov
Version: 0.36
State: Ready
Last upload: 2009, Mars 02
Inclusion date: ???
Depends on:
Fulfill review criteria checked by : ??? At:
- Missing criteria
  - C1
Pre-reviewed by : ??? people
Review Manager: Edward Diener
Expected review date: April 23, 2011 - May 2, 2011-
Links: Boost Vault
Categories: String And Text Processing
Description: Extensible framework for a uniform approach to type-to-type conversions in general. It builds on the lexical_cast past experience, offers the already familiar conversion functionality and more:

simple and better/safe conversion-failure check;
throwing and non throwing conversion-failure behavior;
support for the default value to be returned when conversion fails;
formatting support based on the standard I/O Streams and the standard (or user-defined) manipulators (like std::hex, std::scientific, etc.);
locale support;
support for boost::range-compliant char and wchar_t-based string containers (std::string, std::wstring, char const*, wchar_t const*, char array[], std::vector<char>, etc.);
no DefaultConstructibility requirement for the Target type;
room to grow.

Boost.CounterTree

Author(s): Francisco José Tapia
Version:
State:
Last upload:2010 September 27
Links: Boost Vault
Categories: Containers
Description: Binary trees with access by position like the vectors

Boost.Coroutines

Author(s): Giovanni P. Deretta
Version:
State:
Last upload:2009 December 01
Links: Boost Sandbox Boost Vault Download Stack corruption bug patch
Categories: Concurrent Programming
Description: The Boost.Coroutine library contains a family of class templates that wrap function objects in coroutines. Coroutines are a generalization of subroutines that can return and be reentered more than once without causing the destruction of automatic objects.

Coroutines are useful whenever it is necessary to keep state across a function call, a job usually reserved to stateful function objects.

Boost.Creasing

Author(s): Grant Erickson
Version:
State:
Last upload:
Inclusion date: ???
Depends on:
Fulfill review criteria checked by : ??? At:
- Missing criteria
  - C1
Pre-reviewed by : ??? people
Review Manager: Needed
Expected review date: ???
Links: Boost Vault
Categories: Algorithms
Description:

Boost.Crypto

Author(s): Kasra
Version:
State: (This is not even at beta stage targeted for suggestions and etc ONLY)
Last upload:2009 Jan 20
Links: Boost Vault
Categories: DataCommunication
Description: A library which provides larger number of secure and cryptographic services to the system.

Boost.Dataflow

Author(s): Stjepan Rajko
State: Rewriting ongoing
Version:
Last upload:
Links: Documentation Boost Sandbox
Categories: DataCommunication
Description: Dataflow is a generic library for dataflow programming. Dataflow programs can typically be expressed as a graph in which vertices represent components that process data, and edges represent the flow of data between the components. As such, dataflow programs can be easily reconfigured by changing the components and/or the connections.

Boost.Egg

Author(s): Shunsuke Sogame
State:
Version: 0.91.0
Last upload: 30 Mars 2008
Links: Documentation SVN repository Boost Vault
Categories: Function Objects And Higher-order Programming
Description: Egg is a header-only library for building Polymorphic Function Object which can be used with Boost.Lambda. Such a function object is called a Major Function Object. Egg mainly provides three components:
- Function Builders which build Little Functions into Major Function Objects.
- Function Adaptors which take Polymorphic Function Objects then return adapted ones.
- Function Objects which are ports of famous function templates.

Boost.Endian

Author(s): Tomas Puverle
Version:
State: On going
Last upload:2010 May 26
Links: Download
Categories: Portability
Description: The highlights of the library are the following:
- Very simple interface: swap<machine_to_little/big>(), swap_in_place<machine_to_little/big>()
- Support for built-in and user-defined data types and ranges thereof. E.g. you can swap ranges of structs containing/deriving from other structs
- endian::iterator, which will iterate across a range swapping values as necessary. It works with any swappable type.

Boost.Euclid

Author(s): Andreas Harnack
Version: 0.0.3
State:
Last upload:2008 Nov 26
Links: Boost Vault
Categories: Math And Numerics
Description: Euclidean vector class templates providing Orientational analysis on geometrical dimensions.

Boost.Extension

Author(s): Jeremy Pack
Version:
State:
Last upload:2008 Nov 26
Links: Blog Download Headers Boost Sandbox Libs Boost Sandbox
Categories: Reflective Programming
Description: The Boost.Extension library has been developed to ease the development of plugins and similar extensions to software using shared libraries. Classes, functions and data can be made available from shared libraries and loaded by the application.

Boost.Explore

Author(s): Jeff Garland, Jared McIntyre
Version:
State:
Last upload:2008 Mars 22
Links: Boost Sandbox
Categories: Containers Input/Output
Description: Boost.Explore is a library that provides for the output of data from containers or ranges.

Boost.Generic

Author(s): Matt Callabrese
Version:
State:
Last upload:2008 Mars 22
Links: http://github.com/boostcon/2011_presentations/raw/master/thu/Boost.Generic.pdfPresentation
Categories: Generic Programming
Description: Boost.Generic (not a part of boost) is a C++0x library intended to replace BCCL as a way of specifying concepts and concept maps as close as possible to the withdraw C++0x Concepts.

Boost.Fsm

Author(s): Andrey Semashev
State:
Version:
Last upload:
Links: Boost Vault
Categories: Data Structures
Description:The Boost.FSM library is an implementation of FSM (stands for Finite State Machine) programming concept.

There are many cases when a developer would like to distinguish behavior of a given object depending on some conditions or its internal state. For example, while developing software to control an charging turnstile a programmer would like to separate states in which the turnstile may persist: an idle state, when the device awaits for another passenger that would like to pass; a processing state, when the passenger have come and put his ticket into the device; and the passing state, when the turnstile lets the passenger pass through. In fact, each state describes a different reaction of the machine at the same events. That's why a passenger may only pass after paying for ticket. Obviously, the turnstile have to be able to change its internal state in order to function properly, this is called state switching or transitions between states (or just transitions for short). This implementation is aimed to ease the creation of such state machines in C++. It supports constructing passive automatons (which means that every action the machine performs is a response to some external event) with finite number of states and finite number of transitions (that is why they are called finite state machines). The main goals of the library are:

Simplicity. It should be very simple to create state machines using this library.
Performance. The state machine infrastructure should not be very time and memory-consuming in order to be applicable in more use cases.
Extensibility. A developer may want to add more states to the existing state machine, for example, the maintenance state for the turnstile mentioned above, and this addition should be relatively safe since it shouldn't interfere with the existing states. The developer should also be able to specify additional transitions and events for the machine with minimum modifications to the existing code.

Boost.Hash

Author(s): Scott McMurray [mailto:me22.ca+boost-AT-gmail.com>
Version:
State: Ongoing
Last upload:
Links: sandbox docs
Categories: Algorithm
Description: Concepts for general hashing, with generic implementations of cryptographic hashes (like MD5 and SHA-384) and checksums (like Adler).

Boost.Identification

Author(s): Joel Falcou
Version: v0.3
State:
Last upload: 2009 26 June
Links: Boost Vault
Categories: Utilities
Description: Run-time display of type description as a human-readable string

Boost.Integer.Endian.Ext

Author(s): Vicente J. Botet Escribá, Beman Dawes
Version: 0.1.0
State: Stable
Last upload:2010 June 20
Links: Boost Sandbox Documentation
Categories: Portability
Description: This is an extension of the Beman's Boost.Integer.Endian able to work with endian aware types, used to convert between types with different endian or even to carry on with arithmetic operations, adding support ofr aligned endian unaware types.Boost.Integer.Endian.Ext provides:
- Endian packs
  - Big endian | little endian | native endian byte ordering.
  - Signed | unsigned
  - Unaligned | aligned
  - 1-8 byte (unaligned) | 2, 4, 8 byte (aligned)
  - Choice of integer value type
- Endian integers with the whole set of arithmetics operators.
- Operators <= and => for unformatted binary (as opposed to formatted character) stream insertion and extraction of built-in, std::string types and of endian types.
- Views of aligned endian unaware integer types as endian packs or endian integers so we can make endian conversion.
- Generic in place conversion between different endian formats.
  - Very simple interface: convert_to/from<endiannes domain>(),
  - Support for built-in and user-defined data types view as fusion sequences.

Boost.Interfaces

Author(s): Jonathan Turkanis
Version:
State:
Last upload: 2004
Links: Boost Sandbox
Categories: Patterns
Description: Boost.Interfaces provides a macro-based Interface Definition Language (IDL) which can be used to define C++ class types called interfaces. An interface is a lightweight value type associated with a set of named function signatures. An interface instance can be bound at runtime to any object which implements the interface, i.e., to any object of a type with accessible non-static member functions having the same name and signature as the set of functions associated with the interface. The functions of the bound object can then be invoked through the interface instance using the “dot” operator. Binding is completely non-intrusive: the object's type need not declare any virtual functions or derive from any particular base class.

Boost.InterThreads

Author(s): Vicente J. Botet Escribá
Version: 0.1.3
State: Not ready. Needs to cleanup
Last upload: 2009 April 02
Links: Boost Vault Boost Sandbox Documentation
Categories: Concurrent Programming
Description: Boost.InterThreads extends Boost.Threads adding some features:
- thread decorator: thread_decorator allows to define setup/cleanup functions which will be called only once by thread: setup before the thread function and cleanup at thread exit.
- thread_decorator can now decorate a nullary function in addition to a callable function
- thread specific shared pointer: this is an extension of the thread_specific_ptr providing access to this thread specific context from other threads. As it is shared the stored pointer is a shared_ptr instead of a raw one.
- thread keep alive mechanism: this mechanism allows to detect threads that do not prove that they are alive by calling to the keep_alive_point regularly. When a thread is declared dead a user provided function is called, which by default will abort the program.
- thread tuple: defines a thread group where the number of threads is know statically and the threads are created at construction time.
- set_once: a synchronizer that allows to set a variable only once, notifying to the variable value to whatever is waiting for that.
- thread_tuple_once: an extension of the boost::thread_tuple which allows to join the thread finishing the first, using for that the set_once synchronizer.
- thread_group_once: an extension of the boost::thread_group which allows to join the thread finishing the first, using for that the set_once synchronizer.

thread_decorator and thread_specific_shared_ptr are based on the original implementation of threadalert written by Roland Schwarz.

Boost.Introspection

Author(s): Joel Falcou
Version:
State:
Last upload: 2008 October 10
Links: Boost Vault
Categories: Reflective Programming
Description: Class-level introspection traits class prototype

Boost.Introspection2

Author(s): Jean-Louis Leroy
Version:
State:
Last upload: 2008 November 04
Links: Boost Sandbox
Categories: Reflective Programming
Description: Class-level introspection traits class prototype

Boost.Lexer

Author(s): Ben Hanson
Version: v0.2
State: Not ready. Seems Lexer is been rewritten.
Last upload: 2009 November 24
Inclusion date: ???
Depends on:
Fulfill review criteria checked by : ??? At:
- Missing criteria
  - C1
Pre-reviewed by : ??? people
Review Manager: Eric Niebler
Expected review date: ???
Links: Boost Vault
Categories: String And Text Processing
Description: A programmable lexical analyser generator inspired by 'flex'. Like flex, it is programmed by the use of regular expressions and outputs a state machine as a number of DFAs utilising equivalence classes for compression.

Boost.LUID

Author(s): Vicente J. Botet Escribá
Version: 0.0.0
State: Prototype
Last upload: 2009 Fev 16
Categories: Data Structures
Links: Boost Sandbox Documentation
Description: Boost.LUID simplifies the generation of locally unique identifiers in a wide context.

Locally Unique Identifier or LUID is a special type of identifier used in software applications in order to provide a reference number which is unique in a given context (hence, "Locally" in opposition to "Globally" or "Universally"). Each generated LUID is guaranteed to be unique in its context.

LUID could have many applications. Some examples follow: creating unique identifiers in a database tables, network messages may be identified with a LUID to ensure that this messages are associated to a given session, transactions may be identified by LUIDs.

Note. Please let me know other applications of luids you can have.

Reduced identifier size

An attractive feature of LUIDs when compared to alternatives is the minimal size used by this identifiers, that depends on the number of instances a given context can have (usually 4 bytes). This allows to use them in protocols fixing the size of the references exchanged to less that 16 bytes(as it is the case of UUID and GUID). Usually LUIDs are represented by unsigned integers and have an upper bound value.

Usable as random access index in constant time

Another aspect, and not less interesting is that the access to the information they identify can be done in constant time.

Recovering unused identifiers

A first implementation could consists in a monotonic counter.

The drawback of having a small size is that the number of unique identifier is more limited. This limit will finish by been reached if the application runs a long time. To palliate to this, we need a mechanism to recover the unused identifiers once the identified information is removed. Depending on the application the recovered identifiers should be discarded, reused immediately or frozen during a given duration or a number of times.

Usually they are reused in a first reusable first reused order (fifo), but depending on the implementation this could not be always the more efficient policy. So the user can either constraint this fifo order or let undefined this aspect.

Managing the lack of identifiers

In any case we need to manage with the overflow case, i.e. when there are no more free identifiers. The user could prefer an exception, return an invalid value, use errno, or call to a user defined function which could try to recover from this situation, by re dimensioning the upper bound for example.

Ensuring coherency on reusable identifiers

All this seams to work up to the user do not release the same identifiers twice. As this is an expensive aspect, but usually the applications has its own way to do it. If this is not the case the application could ask to the luid generator to ensure that.

Synchronization on multi threaded or multi process applications

The generation of new LUIDs and the recovering of unused LUIDs must be synchronized. So LUID are better adapted to systems where these operations are done in a reduced scope. Depending on this scope: single thread, multi-threaded process or a node,i.e. multiple process, the synchronization mechanisms vary. In a single thread scope no synchronization is needed. Synchronization on a multi-threaded process can be ensured using a thread mutex.

In addition the synchronization can be ensured internally by the generator, or externally by the user, i.e. the user has already a synchronization mechanism.

LUIDs are not adapted to distributed system (multiple nodes generating and recovering luids) because it needs a coordination between the different nodes which will take too much time. UUIDs and GUIDs are more adapted to this situation. Anyway if the size constraint can not be avoided, one of the nodes could play the master role and the others behaves as slaves. Master and slaves need to work together. This library do not pretend to take in account this use case but, could be the base of such approach.

Persistency

Another aspect is the lifetime of the information to be identified by the luids. It can be the lifetime of the process, the host machine lifetime or persists to a shut down of the host machine using the file-system.

Optimization

The last aspect will be the optimization. Different application have different needs, some have space constraints, and mot of the others have speed constraints.

Boost.MapReduce

Author(s): Craig Henderson [cdm (dot) henderson (at) gmail.com]
Version: 0.4
Last upload: February 26, 2009
Links: Boost Vault Boost Sandbox Online documentation
Categories: Concurrent Programming Algorithms
Description: The Boost.MapReduce library is an implementation of the MapReduce programming model for scalable parallel processing across a plurality of CPU cores. The library is implemented as a set of C++ class templates, and is a header-only library. It does, however, depend upon many other Boost libraries, such as Boost.System, Boost.FileSystem and Boost.Thread.

Boost.Mirror

Author(s): Matus Chochlik
Version: 0.4.9
Last upload: August 30, 2010
Links: Boost Vault Boost Sandbox C++0x version online docs for the C++0x version
Categories: Reflective Programming
Description: The aim of the Mirror library is to provide useful meta-data at both compile-time and run-time about common C++ constructs like namespaces, types (and as an important special case typedef-ined types), classes and their base classes and member attributes, instances, etc. and to provide uniform and generic interfaces for their introspection.

Boost.Monotonic

Author(s): Christian Schladetsch
Version:
State: On going
Last upload:
Links: Boost Sandbox
Categories: Memory Containers
Description: Monotonic allocators

Boost.MPL.Ext

Author(s): Larry Evans
Version:
State: draft
Last upload:February 12, 2009
Links: while_ in Boost Vault and_seq in Boost Vault
Categories: Template Metaprogramming
Description: Some MPL extensions

Boost.MSF

Author(s): Marco Costalba
Version: 1.2.2
State:
Last upload: 2008, Juin 07
Links: Boost Vault
Categories: Function Objects And Higher-order Programming
Description: The Boost.multi_signature_function library is an extension of Boost.Function that allows to define a boost::function on more then one signature. The Boost.Function library contains a family of class templates that are function object wrappers. Please refer to Boost.Function documentation for reference.

The Boost.multi_signature_function library could be used as a building block in more complex components. In the example directory are presented a dynamic dispatcher and an object factory.

Boost.Numeric.Odeint

Author(s): Karsten Ahnert, Mario Mulansky
Version:
State: Under development but usable
Last upload: 2010, April 27
Links: [http://svn.boost.org/svn/boost/sandbox/odeint/ Boost Sandbox] Documentation
Categories: Math And Numerics
Description: Odeint is a library for solving ordinary differential equations. It provides explicit methods like Euler, various Runge-Kutta solvers, as well as adaptive step-size integration and the Burlisch-Stoer algorithm. Furthermore, solvers for Hamiltonian systems are implemented. Further development will go in the direction of

implicit solvers, stiff problems and CUDA support.

Boost.NumericBindings

Author(s): Rutger ter Borg, Karl Meerbergen, Krešimir Fresl, and Toon Knapen
Version: v1
State: stable
Last upload: 2009, November 27
Links: Boost Sandbox v1 Documentation V1 Boost Sandbox Documentation
Categories: Math And Numerics
Description: Boost.Numeric_Bindings is a C++ library for numeric computing. It is a generic layer between data containers and linear algebra algorithms.

For the data container part, it supports both compile-time statically sized and run-time dynamically sized vectors, matrices, through a traits system. Currently it includes traits for C-arrays, for standard vectors, for uBLAS' containers, Eigen containers, TNT, Boost.Array, to name a few. It offers compile-time inspection, iterators, and views on all mentioned containers.

For the algorithm part, it provides a C++ interface to algorithms offered by BLAS, LAPACK, and more. This covers algorithms from most vendor-provided math libraries, such as the reference BLAS, ATLAS, Intel's MKL, AMD's CML, NVidia's CUDA, etc..

Boost.Overload

Author(s): Marco Cecchetti
Version: 0.3.0
State:
Last upload: 2007, Oct 30
Links: Boost Vault
Categories: Function Objects And Higher-order Programming
Description: Boost Overload behaves as an overloaded Boost Function.

Boost.Persistent

Author(s): Stefan Strasser
Version:
State:
Last upload: 2010 January 03
Links: Documentation
Categories: Persistency Containers
Description: Boost.Persistent introduces the concept of a persistent object. Persistent objects can be accessed through locators, which are similar to pointers, but can refer to objects that are stored on disk. The user only expresses the intention of accessing a persistent object but lets the library decide when and how to perform disk I/O.

The persistent state of the application can be updated in small increments, instead of serializing the whole application state at one point. Those updates are conducted as atomic operations by the library, that are presented to the user either as savepoints or as transactions. The library maintains a consistent application state and recovers it from application and system failures.

Finally, a persistent object can be accessed from multiple transactions in different threads concurrently and independent from each other, making manual synchronization obsolete.

Boost.Plot

Author(s): Jacob Voytko & Paul A. Bristow
Version: v0
State: Under development, especially documentation, but usable.
Last upload: Jan 2009
Links: Boost Plot
Categories: Image Processing
Description: Provides a way of plotting simple 1 and 2D graphs in Scalable Vector Graphic (svg) format directly from C++ code. The graphs are high quality when displayed on a wide variety of display sizes, from mobile phone to big screen, or when printed, but the graph files are tiny and fast enough to be done in near real-time. Fine control of appearance is provided in C++ (but with defaults and optional scaling of axes) so graphs can be produced in a very few lines of code. Current documentation is a mess but Very much improved documentation is nearly complete using Doxygen: meanwhile there are lots of examples.

Boost.Process

Author(s): Boris Schaeling, Ilya Sokolov, Felipe Tanus, Julio M. Merino Vidal
Version: v0.4
State: On going
Last upload: October 08, 2010
Review Manager: Marshall Clow
Expected review date: February 7. 2011 - February 16, 2011
Links: Boost Sandbox Download Documentation
Categories: System
Description: Boost.Process is a library to manage system processes. It can be used to:

create child processes
run shell commands
setup environment variables for child processes
setup standard streams for child processes (and other streams on POSIX platforms)
communicate with child processes through standard streams (synchronously or asynchronously)
wait for processes to exit (synchronously or asynchronously)
terminate processes

Boost.Reflection

Author(s): Jeremy Pack
Version:
State:
Last upload:2008 Aug 08
Links: Blog Download Boost Sandbox Headers Boost Sandbox
Categories: Reflective Programming
Description: The goal of this library is to provide runtime reflection for C++ classes, and to allow the same across shared library boundaries. It is an offshoot of the Extension library, which provides dynamic class loading across shared libraries.

Boost.Reflection does not provide automatic reflection of classes. Instead, the class data must be manually reflected. This does offer some benefits however:

This can result in better performance, since only the necessary functions are reflected.
Arbitrary classes can be reflected without modification.
It is possible to make a reflected interface that is quite different from the original interface.

Boost.RendezVous

Author(s): Vicente J. Botet Escribá
Version: 0.3.2
State: Quite Stable
Last upload: 2009 May 11
Links: Boost Vault Boost Sandbox
Categories: Concurrent Programming
Description: Concurrent components may interact in different ways: they may access the same objects by, for example, executing functions of these objects; or they may communicate directly by executing functions of each other. These library will provide the so-called rendezvous mechanism for handling direct communication between active objects.

Boost.RPC

Author(s): Stjepan Rajko
Version:
State:
Last upload: 2007
Links: Boost Sandbox
Categories: Distribued Programming
Description: This is a prototype framework for a remote procedure call implementation using Boost libraries,

specifically Boost.Asio for network communication, Boost.Serialization for marshaling, and futures for handling of returned values.

The framework supplies both server-side and client side components that allow remote procudure calls to be made, and parameters/results to be marshaled between the client and the server. A remote procedure call is executed as follows:

# on the client, the function id and the arguments are serialized and sent over the network # the server receives the serialized call, unserializes the id and arguments and executes the call # if applicable, the results of the call are serialized and sent back over the network to the client

Boost.RDB

Author(s): Jean-Louis Leroy
Version:
State:
Last upload: 2009 November 25
Links: Boost Vault
Categories: Database
Description: C++ is a statically typed language. sql is also a statically typed language. It looks like they should play ball together.

So how comes that most C++/sql bindings make it possible to write and compile code that contains not-so-subtle errors ? They could be caught at compile time since all the necessary information is there.

Well this is just what this library does.

Boost.RDB provides bindings to various relational database systems. It supports creating and executing SQL statements and retrieving the results by means of C++ objects. Most of the time the resulting syntax is very close to plain SQL. Moreover, Boost.RDB is a good citizen of the type-rich C++ world: all constructs are statically checked, which eliminates the risks of type errors. If your RDB code compiles, then it generates correct SQL. Since everything happens at compile-time, the library delivers performance that is close to hand-written code.

What it's not

Boost.RDB does /not/ hide the database behind an abstraction layer. On the contrary, it ambitions to make the pecularities of each system readily accessible. However, SQL is standardized, and while it's true that few vendors - if any - comply to the standard in every small detail, most of the SQL code uses constructs that are portable between vendors.

Boost.RDB neither attempts to add extra functionality on top of the database (like object-relational mapping). These tasks belong to higher-level libraries, possibly built on top of Boost.RDB.

Boost.RTL

Author(s): Arkadiy Vertleyb, Dmitriy Arapov
Version:
State:
Last upload: 2006 December 06
Links: Boost Sandbox
Categories: Database
Description: RTL is an attempt to create a facility that would be free from the above drawbacks, and make relational tables and relational operations convenient to use from a C++ program.

Boost.Singleton

Author(s):
Version:
State:
Last upload:
Links: [ Boost Sandbox]
Categories: Patterns
Description:

Boost.SmartPtr.UniquePtr

Author(s): Howard Hinnant <hinnant@…>
Version:
State:
Last upload: 2009 Jan 3
Links: Documentation & Download
Categories: Generic Programming
Description: unique_ptr is a class template smart pointer currently in the C++0X CD1 draft. It is intended to be a safer and more flexible replacement for auto_ptr. It represents sole (unique) ownership of a resource such as memory (like auto_ptr).

The actual C++0X unique_ptr makes use of a new C++ language feature called rvalue reference which is similar to our current reference (&), but spelled &&. This emulation is intended to capture most of the behavior of the C++0X unique_ptr but work with C++03 compilers. Furthermore this emulation makes use of boost library facilities and has been placed in the boost namespace. Though at the time of this writing, this library is not part of the official boost library release.

Boost.SafeInt

Author(s): Ziv Levi and Omer Katz
Version: v0.0
State: Draft
Last upload: 2009 June 20
Links: Boost Vault
Categories: Math And Numerics
Description: Safe integer types

StableVector

Author(s): Joaquín M López Muñoz
Version:
State: Draft
Last upload:
Links: Stable Vectors
Categories: Containers
Description: a container mimicking the interface of std::vector except that it provides iterator and reference stability at the expense of losing memory contiguity.

Boost.STM

Author(s): Justin E. Gottchlich , Vicente J. Botet Escribá
Version: 0.1
State: work on going
Last upload: 2009 Sep 19
Links: Web Site Downloads Boost Sandbox Documentation
Categories: Concurrent Programming
Description: Transactional memory (TM) is a new parallel programming mechanism that reduces the complexity of parallel programming. TM reduces parallel programming complexity by abstracting away the necessary synchronization mechanisms from the parallel code, allowing the programmer to write parallel applications without worry of deadlocks, livelocks or race conditions.

Transactional memory is an active research interest for many academic and industry institutions with many open questions about its behavior.

TBoost.STM is a C++ lock-based software transactional memory (STM) library. Our approach to STM is to use only native language semantics while implementing the least intrusive, most type-safe object oriented solution possible.

TBoost.STM provides:

Optimistic concurrency
ACI transactions

o Atomic: all operations execute or none do o Consistent: only legal memory states o Isolated: other txes cannot see until committed

Language-like atomic transaction macro blocks
Closed, flattened composable transactions
Direct and deferred updating run-time policies
Validation and invalidation conflict detection policies
Lock-aware transactions
Programmable contention management, enabling programmers to specify forward progress mechanisms
Isolated and irrevocable transactions for transactions that must commit (i.e., I/O transactions)

Boost.Sync

Author(s): Vicente J. Botet Escribá
Version: 0.0.0
State: work on going
Last upload: 2010 September 12
Links: Boost Sandbox Documentation
Categories: Concurrent Programming
Description: Unifying Boost.Thread and Boost.Interprocess synchronization mechanisms

The goal of Boost.Sync is to remove the syntactic differences between the synchronization mechanisms of the Boost.Thread and Boost::Interprocess libraries and be a holder of common mechanism and algorithms working on the common concepts.

The differences I have identified up to now are:

The scoped locks can be initialized with static const variables in order to overload the constructor for lock adoption, lock deferral or try to lock. Even if the name of these variables is almost the same, these variables live in different namespace. It would be nice if both libraries use the same type and the same variables.

The shared mutex provide similar service with different names. In addition each implementation provide some functions that are not provided by the other.

The scoped locks live in a different namespace and some have different names with the same semantic. IMO these should be shared.

The exception thrown lives in a different name space and different names with equivalent semantics If we follow the C++0x standard the exception to throw should be system_error. Both libraries could adapt his hierarchy to Boost.System. The drawback is that users of Boost.Thread and Boost.Interprocess will need to link with Boost.System which is not a header only library.

The move semantics (&&) of Boost.Thread should be adapted to the forthcoming Boost.Move library as soon as integrated on the release branch. Boost.Interprocess uses already a detail implementation equivalent to the provided by Boost.Move, so the change will be simpler.

Adapt both libraries interface to use Boost.Chrono, which is yet a non header only library, once it is accepted.

Of course, this needs some adaptation of the Thread and Interprocess libraries.

Boost.Sync will contain

lockable concepts and locks concepts.
lockables traits,
null_mutex and null_condition classes,
Add some common locks as
- strict_lock, nested_strict_lock,
- reverse_lock, nested_reverse_lock,
A polymorphic lockable hierarchy.

Boost.Synchro

Author(s): Vicente J. Botet Escribá
Version: 0.3.2
State: work on going
Last upload: 2009 May 11
Links: Boost Vault Boost Sandbox Documentation
Categories: Concurrent Programming
Description:
- A uniform usage of Boost.Thread and Boost.Interprocess synchronization mechanisms based on lockables(mutexes) concepts and locker(guards) concepts.
  - lockables traits and lock generators,
  - generic free functions on lockables as: lock, try_lock, ...
  - locker adapters of the Boost.Thread and Boost.Interprocess lockers models,
  - complete them with the corresponding models for single-threaded programs: null_mutex and null_condition classes,
  - locking families,
  - semaphore and binary_semaphore,
  - condition_lockable lock which put together a lock and its associated conditions.
- A coherent way exception based timed lock approach for functions and constructors,
- A rich palette of lockers as
  - strict_locker, nested_strict_locker,
  - condition_locker,
  - reverse_locker, nested_reverse_locker,
  - locking_ptr, on_dereference_locking_ptr,
  - externally_locked,
- array_unique_locker on multiple lockables.
- Generic free functions on multiple lockables lock, try_lock, lock_until, lock_for, try_lock_until, try_lock_for, unlock * lock adapters of the Boost.Thread and Boost.Interprocess lockable models,
  - lock_until, lock_for, try_lock_until, try_lock_for
- A polymorphic lockable hierarchy.
- High-level abstractions for handling more complicated synchronization problems, including

o monitor for guaranteeing exclusive access to an object.

Language-like Synchronized Block Macros

Boost.Task

Author(s): Oliver Kowalke
Version: 0.2.1
State: Quite Stable
Last upload: 2009 June 25
Inclusion date: ???
Depends on: Boost.Fiber, Boost.TaskLet, Boost.Atomic
Fulfill review criteria checked by : ??? At:
- Missing criteria
  - C1
Pre-reviewed by : ??? people
Review Manager: Vicente Botet
Expected review date: ???
Links: Boost Vault Boost Sandbox GitHub Sandbox
Categories: Concurrent Programming
Description: execute tasks in threadpool, in new thread or as sub-task and let the result be transfered via a future. support task interruption, work-stealing and fork/join semantics

Boost.TimerQueue

Author(s): John Q. Smith
Version: 0.1
State: On going
Last upload: 2009 June 03
Links: Boost Vault
Categories: Concurrent Programming
Description: Timer Queue is a library that allows you to specify some arbitrary future time at which to be handed back a value that you supply at timer creation.

Boost.ThreaderJoiner

Author(s): Vicente J. Botet Escribá
Version: 0.4.1
State: Quite Stable
Last upload: 2009 Mars 01
Links: Boost Vault Boost Sandbox
Categories: Concurrent Programming
Description: Threader/Joiner as proposed by Kevlin Henney `Preliminary Threading Library Proposal for TR2

Boost.Tokenmap

Author(s): Slawomir Lisznianski
Version:
State:
Last upload: 2010 April 21
Links: Boost Sandbox Boost Documentation
Categories: Containers, Data Structures
Description: A tokenmap is a data structure that uniquely maps integer keys (called tokens) with values.

Unlike typical dictionary-like containers such as std::map or boost_unordered, tokenmap generates the keys for stored values. The keys are random in appearance yet have the property of allowing the container to perform very efficient look-ups -- in the order of indexing within a C-array.

tokenmaps have the following properties:

No two tokens map to the same value; in essence, tokenmap is a perfect hash container.
The returned tokens are stable (a token will always map to a corresponding value regardless of how the tokenmap was modified since the token was generated).
Lookups are very efficient compared to std::map find. For example, when looking up a value in a 1,000,000-elements container, tokenamp outperforms std::map by about 30 times.

Boost.Tree

Author(s): Bernhard Reiter
Version:
State:
Last upload: 2008 Nov 30
Links: Boost Sandbox
Categories: Containers
Description: TR2 Proposal text: Tree Structures and Related Concepts for the C++ Standard Library (TR2)

Boost.TypeErasure

Author(s): Steven Watanabe
Version:
State:
Last upload:2011 Mai 22
Links: Boost Vault
Categories: Generic Programming
Description: C++ provides runtime polymorphism through virtual functions. They are a very useful feature, but they do have some limitations.

They are intrusive. In generic programming, we can design an interface which allows third-party types to be adapted to it.
They require dynamic memory management. Of course, most of the problems can be avoided by using an appropriate smart pointer type. Even so, it still acts like a pointer rather than a value.
Virtual functions' ability to apply multiple independent concepts to a single object is limited.

The Boost.TypeErasure library solves these problems allowing us to mirror static generic programming at runtime.

Boost.Unicode

Author(s): Graham Barnett & Rogier van Dalen
Version:
State:
Last upload: February 12, 2009
Links: Boost Vault
Categories: String And Text Processing
Description: The Boost Unicode library aims to bring Unicode to C++ without requiring intricate knowledge of the Unicode standard, while allowing Unicode experts to do advanced things.

Boost.Unicode2

Author(s): Mathias Gaunard
Version: 0.1
State:
Last upload: August 27, 2009
Links: Boost Vault
Categories: String And Text Processing
Description: This library aims at providing the foundation tools to accurately represent and deal with natural text in C++ in a portable and robust manner, so as to allow internationalized applications, by implementing parts of the Unicode Standard.

This library is environment-independent and deliberately chooses not to relate to the standard C++ locale facilities as well as the standard string facilities, judged ill-suited to Unicode.

The current version is locale-agnostic, but a subsystem for tailored locale behaviour may be added in the future.

Boost.XInt

Author(s): Chad Nelson
Version: 0.6
State:
Last upload: 2010, Jun 19
Review Manager: Vladimir Prus
Expected review date: March 2, 2011 - March 12, 2011
Links: Boost Sandbox Boost Documentation
Categories: Math And Numerics
Description: It's a C++ library that lets your program handle much, much larger integer numbers than the built-in int, long, or even long long types, and handle them using the same syntax that C and C++ use for the built-in integer types.

The maximum size of the integer is limited only by the memory available to store it. In practice that's millions of hexadecimal digits, so it's effectively infinite.

Boost.XML

Author(s): Stefan Seefeld
Version:
State:
Last upload: 2008
Links: Boost Sandbox
Categories: String And Text Processing XML
Description: XML parser

Other Open Source libraries

This page contains other libraries that work well with Boost.

ASL

Author(s): Sean Parent and Mat Marcus - Adobe
Version: 1.0.39
State: Released
Last upload: November 6, 2008
Links: Home page
Description: Adobe Source Libraries (ASL) provides peer-reviewed and portable C++ source libraries. The libraries are intended to be widely useful, leveraging and extending both the C++ Standard Library and the Boost Libraries.

async

Author(s): Edd Dawson
Version: 0.2.3
State:
Last upload: 15 January 2008
Links: Web Site Download
Categories: Concurrent Programming
Description: async is a C++ library to allow the calling of functions and functors in an asynchronous manner, thereby making it easier to improve the level of concurrency and parallelism in your applications.

coco

Author(s): Edd Dawson
Version: 0.2.0
State:
Last upload: 23 Feb 2008
Links: Web Site Download
Categories: Concurrent Programming
Description: coco is a library that implements the Boost.Thread interface but is written in terms of the operating system’s native cooperative threading mechanism, whether that be Fibers on Windows, or the <ucontext.h> functions on POSIX machines.

This means that multi-threaded programs written using Boost.Thread can now be run in a single thread. This is useful for debugging and testing purposes, where it is necessary to look at algorithmic correctness in isolation from correctness of synchronisation.

Poet

Author(s): Frank Mori Hess
Version:
State:
Last upload: June 25, 2008
Links: Home Page
Categories: Concurrent Programming
Description: libpoet is a C++ parallel programing library. It provides support for easily creating active objects, creating monitor objects, and automatically validating mutex locking order.

Active objects provide concurrency and thread-safety, since each active object executes in its own thread. Futures are employed to communicate with active objects in a thread-safe manner. To learn more about the active object concept, see the paper "Active Object, An Object Behavioral Pattern for Concurrent Programming." by R. Greg Lavender and Douglas C. Schmidt. Some of the more important active object classes in libpoet are poet::active_function, poet::future, and poet::scheduler.

Monitor objects provide thread-safety via automatically locked access to an object. See the paper "Monitor Object, An Object Behavioral Pattern for Concurrent Programming" by Douglas C. Schmidt for more information about monitor objects. The poet::monitor_ptr, poet::monitor, and poet::monitor_base classes in libpoet provide support for monitor objects.

Finally, the poet::acyclic_mutex class provides a wrapper for mutex classes which adds automatic validation of a program's mutex locking order. Following a consistent locking order ensures your program will not deadlock due to problems such as "deadly embrace" or the "dining philosophers" problem.

TBB

Author(s): Intel
Version: 2.1
State: stable release
Last upload: June 7, 2008
Links: Home page
Categories: Concurrent Programming
Description: Intel® Threading Building Blocks (TBB) offers a rich and complete approach to expressing parallelism in a C++ program. It is a library that helps you take advantage of multi-core processor performance without having to be a threading expert. Threading Building Blocks is not just a threads-replacement library. It represents a higher-level, task-based parallelism that abstracts platform details and threading mechanism for performance and scalability and performance.

tscb

Author(s): Helge Bahmann
Version: 0.1
State:
Last upload: 2008 Nov 23
Links: Documentation+Download
Categories: Concurrent Programming
Description: Thread-safe callback services.

This library provides classes for notifications via callbacks in multi-threaded programs. In particular, it provides the following services:

Signals and slots: signal_proxy provides an interface through which interested receivers can connect/disconnect callback functions at runtime. signal provides an implementation of this interface and provides senders a mechanism to notify interested receivers, passing specified arguments to each callback function.
I/O readiness: ioready_service provides an interface through which interested receivers can register/deregister for notification on I/O readiness events (i.e. file descriptor ready for reading/writing; cf. poll/select). ioready_dispatcher provides an implementation of this interface that allows waiting (with timeout) for and fetching the required information from the operating system and notifying registered receivers.
Timers: timer_service provides an interface through which interested receivers can register/deregister for notification at specific points in time. timer-queue_dispatcher provides an implementation of this interface, keeping track of all pending timers, deadline when next timer is due, and "premature interruption" if the deadline must be invalidated (e.g. due to a newly-added timer).
Compound event dispatching (or "reactor-style" operation): posix_reactor_service combines the ioready_service, timer_service and workqueue_service interfaces. posix_reactor provides an implementation of this interface and performs all required operations of delivering all requested notifications.

The implementations in this library provide strong thread-safety guarantees, are reentrant, deadlock-free and provide strong consistency guarantees. See section Concurrency and reentrancy below for an exact definition of the guarantees.

Libraries Wish list

This page contains libraries that people have requested of Boost (mostly on the developer's mailing list). If you're looking for a project, this is a good place to start.

Accumulators.Ext

Suggested by: Vicente J. Botet Escribá
Categories: Math And Numerics
Description: Adding sliding, dependable and cyclic accumulators to Boost.Accumulators.

The accumulator library allows to determine dependency between accumulator, but not between accumulator_sets. I would like to define an accumulator_set c so when we cumulate in two others c1 and c2 accumulator_set we cumulate also in c, some thing like:

typedef dependable_accumulator_set <double, ...> dependable_acc_type;

dependable_acc_type c1, c2;
dependable_acc_type c=c1+c2

dependable_acc_type c3;

c+=c3;

c1(1);
c2(1);
c3(2);
assert(count(c)==3);
assert(sum(c)==4);

How dependable_accumulator_set can be defined? Here follows the interfaces of such a class and the pseudo code, I've named the class dependable_accumulator_set, sorry but I have not found a shorter and better name (may be observed/listened?)

template <typename T, typename F, typename W>
class dependable_accumulator_set : public acumulator_set<T,F,W>
{
public:
    dependable_accumulator_set();
    void add_dependent(dependable_acumulator_set&);
    void remove_dependent(dependable_acumulator_set&);

    template<typename A1>
    void operator ()(A1 const &a1) {
        for (acc in dependents) {
            acc(a1);
        }
        this->accumulator_set_type::operator()(a1);
    }
    dependable_accumulator_set<T,F,W>& operator+=(dependable_accumulator_set<T,F,W>);
    dependable_accumulator_set<T,F,W>& operator-=(dependable_accumulator_set<T,F,W>);
};

template <typename T, typename F, typename W>
dependable_accumulator_set<T,F,W> 
operator+()(dependable_accumulator_set<T,F,W>,dependable_accumulator_set<T,F,W>);

Another variant could be also to have a temporary accumulator that cyclically push its current value on another accumulator.

It will also interesting to have a dependable and cyclic accumulator set. It would be great to integrate these features on a unique class (accumulator_set?) in a clean way.

template <typename T, typename F, typename W, 
          typename DependablePolicy, 
          typename CyclicPolicy>
class accumulator_set;

Association

Suggested by: Vicente J. Botet Escribá
Categories:Data Structures
Description: Intrusive bidirectional associations.

Cloner

Suggested by: Vicente J. Botet Escribá
Categories: Data Structures
Description: Clone framework

CallStack

Suggested by: Paulius Maruška
Categories: Debug
Description: Provide one api, which would work on all platforms, to get the callstack info.

ConstraintsProgramming

Suggested by: Vicente J. Botet Escribá
Categories: []
Description: Constraints programming is a programming paradigm where relations between variables are stated in the form of constraints. Constraints differ from the common primitives of imperative programming languages in that they do not specify a step or sequence of steps to execute, but rather the properties of a solution to be found. This makes Constraint Programming a form of declarative programming.

typedef bounded<int, closed<1>, closed<2> > domain;
problem_solver<domain, domain> p;
p.add_constraint(_1 + _2 == 3);
for {problem::iterator it = p.solutions(); it != p.end(); ++it) {
    domain a, b;
    tie(a,b) = *it;
    std::cout << "[" << a << ", " << b << "]" << std::endl;
}

Databases

Suggested by: elfring
Categories: Database
Description: a library for database interaction.

Enums

Suggested by: Vicente J. Botet Escribá
Categories: Data Structures
Description: Enums traits.

EnumSet

Suggested by: Vicente J. Botet Escribá
Categories: Containers
Description: STL Set interface for enums.

EnumArray

Suggested by: Vicente J. Botet Escribá
Categories: Containers
Description: Array indexed by Enums.

Frames

Suggested by: Vicente J. Botet Escribá
Categories: Input/Output
Description: Library based on an extension of the Archive concept making it bidirectional.

From wikipedia "A frame is a data packet of fixed or variable length which has been encoded by a data link layer communications protocol for digital transmission over a node-to-node link. Each frame consists of a header frame synchronization and perhaps bit synchronization, payload (useful information, or a packet at higher protocol layer) and trailer. Examples are Ethernet frames and Point-to-point protocol (PPP) frames."

The Boost.serialization saving archive concept allows to save serializable data at the end of the archive, and the loading archive concept allows to read serializable data from the beginning of the archive. The saving frame concept will allows to save serializable data either at the end or the begin of the frame, and the loading frame concept allows to read serializable data from the beginning or the end of the archive. I'm not sure which syntax will be the more appropriated. The serialization library use the <<, >>, and & operators that are associative from left to right. We need the equivalent operators from right to left. <<=, >>=, and &= seams to be the more natural candidates but I don't know if it is correct in C++ to define this operators with this prototype

template <typename T> frame& operator<<=(const T&, frame&);
template <typename T> frame& operator>>=(const T&, frame&);
template <typename T> frame& operator&=(const T&, frame&);

h1 >>= h2 >>= sf << t2 << t1

is equivalent to

(h1 >>= (h2 >>= ((sf << t2) << t1)))

and should be equivalent to

sa & h1 & h2 & t2 & t1

if sf and sa were empty.

The main difference is that we can do it hierarchically. The top layer will create a frame, and serialize its own information elements.

frame sf;
h_n >>= sf  << p_n << t_n;

Then this top layer will use a primitive of the lower level having as parameter the frame as payload.

primitive_n-1(sf);

A primitive at the k level will add its own header and trailer information element to the payload of the upper level

void primitive_k(frame& sf) {
    // ...
    h_k >>= sf  << t_k;
    // ...
    another_primitive_k_1(sf);
    // ...
}

So the frame allows to serialize top-down. To get the same result with the archive concept the serialization must be done bottom-up, needing to chain each one of the information element in a list and only when we have all off them we can start the serialization. I think that the frame approach should be more efficient because it avoid to store in dynamic memory the information elements to be serialized, instead they are serialized directly.

Loading a frame works as loading an archive, except that we can load also at the end of the frame. This avoids to load the complete archive to load the trailer of the lower levels.

lf >>= h_1;
// ...
t_1 << lf;

In addition, it would be great to have saving/loading frames (I'm not sure but I think that an archive can not be saving and loading at the same time). The same frame can be used as loading, analyzing only some lower levels, and as saving in order to construct other lower levels. This will be very useful for gateways and routers.

| L4 |<------------------------------>| L4 |
| L3 |    |     ADAPTATION     |      | L3 |
| L2 |<-->| L2 |          | X2 | <--> | X2 |
| L1 |<-->| L1 |          | X1 | <--> | X1 |

It would be great also that the same data that can be serialized on archives, could be serializable on a frame using the same save function. But this works only when we save at the end of the frame. Let me see this using a little example: Class C has 3 information elements to serialize (a, b and c). So the save functions could be something like

template <typename ARCHIVE>
void C::save(ARCHIVE& sa) {
    sa & a & b & c;
}

This save function works well from left to right, but can not be used when saving at the beginning of a frame, because the expected result when saving at the beginning is

a b c sa

but the result will be

c b a sa

So unfortunately we need a different save function

template <typename FRAME>
void C::save(FRAME& sa, begin_tag&) {
    a >>=  b >>= c >>= sa;
    // a >>=  (b >>= (c >>= sa));
}

ObjectRole

Suggested by: Vicente J. Botet Escribá
Categories: Containers Data Structures
Description: Change the behaviour of an object depending on the roles it plays.

Quartets

Suggested by: Vicente J. Botet Escribá
Categories: Containers Data Structures
Description: Quartet are half an octet, i.e. 4 bits taking values from 0..15, and usually represented by chars '0'-'9' 'A'-'F'. There are some container specializations as std::string, std::vector and boost::array that could be of interest to some applications. They are also used when a decimal number is encoded using the BCD format (binary coded decimal) or to encode telephone numbers.

SpreadSheet

Suggested by: Vicente J. Botet Escribá
Categories: []
Description: Allows to manage with the underlying concepts of a Spreadsheet but without displaying them.

Defines cells that can be organized in a classical grid consisting of rows and columns, or any other structure as for example a tree. Each cell could contains alphanumeric text or numeric values but can also contain any other value. A spreadsheet cell may alternatively contain a formula that defines how the contents of that cell is to be calculated from the contents of any other cell (or combination of cells) each time any cell is updated.

It seems natural to use Boost.Proto to define the DSL for the cell formulas.

cell<int> c1, c2, c3;
c1 = 1;
c2 = 2;
c3 = c1 + c2;
std::cout<< c1.get() << ", " << c2.get() << ", " << c3.get() << std::endl;

sheet sh(2,3);
sheet::cell<int> c01(sh,0,1), c02(sh,0,2), c03(sh,0,3);
c01 = 1;
c02 = 2;
c03 = rel_cell(c03,0,1)+rel_cell(c03,0,2);
std::cout<< c01.get() << ", " << c02.get() << ", " << c03.get() << std::endl;
c11 = 5;
c12 = 8;
c13 = c03.copy(); 
std::cout<< c11 << ", " << c12 << ", " << c13 << std::endl;

Abandoned

Boost.ConceptTraits

Author(s): Terje Slettebø and Tobias Schwinger
Version:
State:
Last upload: 2004 September 12
Categories: Correctness And Testing Language Features Emulation
Links: Documentation Original Download

Last Download

Description:Overload on Concepts of template parameter types, using enable_if and some class traits.

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